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Setting an int to Infinity in C++
...int's maximum value:
#include <limits>
// ...
int a = std::numeric_limits<int>::max();
Which would be 2^31 - 1 (or 2 147 483 647) if int is 32 bits wide on your implementation.
If you really need infinity, use a floating point number type, like float or double. You can then get inf...
Quickly reading very large tables as dataframes
...rom csv/tab-delimited files directly into R. See mnel's answer.
Using read_table in readr (on CRAN from April 2015). This works much like fread above. The readme in the link explains the difference between the two functions (readr currently claims to be "1.5-2x slower" than data.table::fread).
r...
How do I create directory if none exists using File class in Ruby?
... are not already present:
require 'fileutils'
dirname = File.dirname(some_path)
unless File.directory?(dirname)
FileUtils.mkdir_p(dirname)
end
Edit: Here is a solution using the core libraries only (reimplementing the wheel, not recommended)
dirname = File.dirname(some_path)
tokens = dirname....
Android ImageView Zoom-in and Zoom-Out
...wn(int keyCode, KeyEvent event) {
if(keyCode==KeyEvent.KEYCODE_DPAD_UP){
// zoom in
zoomControler+=10;
}
if(keyCode==KeyEvent.KEYCODE_DPAD_DOWN){
// zoom out
zoomControler-=10;
...
Precision String Format Specifier In Swift
...
a simple way is:
import Foundation // required for String(format: _, _)
print(String(format: "hex string: %X", 123456))
print(String(format: "a float number: %.5f", 1.0321))
share
|
impro...
Split string in Lua?
...%s, like %D is the negation of %d. Additionally, %w is equal to [A-Za-z0-9_] (other characters might be supported depending on your locale).
– Lars Gyrup Brink Nielsen
Jan 2 '14 at 22:00
...
Convert UTC date time to local date time
...
function localizeDateStr (date_to_convert_str) { var date_to_convert = new Date(date_to_convert_str); var local_date = new Date(); date_to_convert.setHours(date_to_convert.getHours()+local_date.getTimezoneOffset()); return date_to_convert.toString();...
How to print struct variables in console?
...se2{
Page: 1,
Fruits: []string{"apple", "peach", "pear"}}
res2B, _ := json.Marshal(res2D)
fmt.Println(string(res2B))
That would print:
{"page":1,"fruits":["apple","peach","pear"]}
If you don't have any instance, then you need to use reflection to display the name of the field of a g...
Python add item to the tuple
..., works the same in python3 and python2.7.
– ILMostro_7
Jun 15 '18 at 11:42
5
...
Force R not to use exponential notation (e.g. e+10)?
...
In rstudio, if you import a dataset and do train_sample_10k = format(train_sample_10k,scientific=FALSE) and reload, it will change scientific notations.
– mixdev
Nov 23 '14 at 5:21
...